Contact lens with phase map display

ABSTRACT

A contact lens includes a transparent material, a substrate material, a light source, an optical system, and a phase map. The transparent material has an eye-side opposite an external side. The eye-side is curved to fit the human eye. The light source is configured to emit illumination light. The optical system is configured to receive the illumination light from the light source and output the illumination light as an in-phase wavefront. The phase map is configured to adjust a phase of the in-phase wavefront to form an image at a retina-distance in response to being illuminated by the in-phase wavefront. The phase map is pre-recorded with a phase pattern that is included in the image.

TECHNICAL FIELD

The present application is related to a U.S. Application entitled“Near-eye Display with Phase Map,” U.S. application Ser. No. 14/724,095,filed on the same day.

TECHNICAL FIELD

This disclosure relates generally to near-eye displays, and inparticular to contact lenses that include phase map displays.

BACKGROUND INFORMATION

Near-eye displays are wearable devices that form a display image in awearer's field of view. Near-eye displays have numerous practical andleisure applications. Aerospace applications permit a pilot to see vitalflight control information without taking their eye off the flight path.Public safety applications include tactical displays of maps and thermalimaging. Other application fields include video games, transportation,and telecommunications.

Since near-eye displays are wearables, improvements in power consumptionand form factor are highly desirable. Conventional near-eye displaysoften include a micro-display and an image relay that includes lensesand/or mirrors to direct the images generated by the micro-display tothe eye of a wearer of the near-eye display. These various opticalcomponents add bulk to the near-eye display. Furthermore, the opticalcomponents must be fabricated with very tight manufacturing tolerancesand also be precisely aligned to maintain the fidelity of the imagegenerated by the micro-display. The optical components must also bedesigned to maintain the colors of the image as the image lightpropagates through the image relay. Therefore, a near-eye display thatreduces the bulk, power consumption, and optical fidelity requirementsof existing near-eye displays is desirable.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the invention aredescribed with reference to the following figures, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified.

FIGS. 1A and 1B illustrate an example near-eye display that includes aphase map, in accordance with an embodiment of the disclosure.

FIG. 2 illustrates an example near-eye display that includes a phasemap, in accordance with an embodiment of the disclosure.

FIG. 3A illustrates an example phase map, in accordance with anembodiment of the disclosure.

FIG. 3B illustrates phase levels of a portion of the pixels in the phasemap illustrated in FIG. 3A, in accordance with an embodiment of thedisclosure.

FIG. 3C illustrates an image generated by a phase map, in accordancewith an embodiment of the disclosure.

FIGS. 4A and 4B illustrate a contact lens that includes a light sourceand a phase map for generating an image directed into the eye of awearer of the contact lens, in accordance with an embodiment of thedisclosure.

FIG. 5 illustrates a system that includes a near-eye display, inaccordance with an embodiment of the disclosure.

FIGS. 6A and 6B illustrate a contact lens that includes a phase map inan eye, in accordance with an embodiment of the disclosure.

FIG. 7 illustrates a Head Mounted Display that includes a phase map, inaccordance with an embodiment of the disclosure.

FIG. 8 illustrates eyeglasses that include a phase map, in accordancewith an embodiment of the disclosure.

DETAILED DESCRIPTION

Embodiments of near-eye displays that include phase maps and systemsthat include near-eye displays are described herein. In the followingdescription, numerous specific details are set forth to provide athorough understanding of the embodiments. One skilled in the relevantart will recognize, however, that the techniques described herein can bepracticed without one or more of the specific details, or with othermethods, components, materials, etc. In other instances, well-knownstructures, materials, or operations are not shown or described indetail to avoid obscuring certain aspects.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present invention. Thus, theappearances of the phrases “in one embodiment” or “in an embodiment” invarious places throughout this specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments.

FIG. 1A illustrates an example near-eye display 100 that includes aphase map 150, in accordance with an embodiment of the disclosure.Near-eye display 100 includes a light source 105, optical system 120,and phase map 150. In one embodiment, light source 105 is a laser diodethat emits visible narrow-band (e.g. 1-2 nm) light. In anotherembodiment, light source 105 is a light-emitting-diode (“LED”) thatemits broader spectrum (e.g. 50 nm band) colored light. The LEDs may bered, green, or blue, for example. In one embodiment, light source 105 isa monochromatic green LED.

Optical system 120 may include various optical components such asdiffractive and refractive lenses, mirrors, filters, and collimators,depending on the specific requirements of the near-eye display. Opticalsystem 120 is configured to receive illumination light 107 emitted bylight source 105 and output the illumination light as in-phase(coherent) wavefront 129. Although in-phase wavefront 129 is coherent,it may not necessarily be collimated. In other words, in-phase wavefront129 may be diverging or converging, in some embodiments. In otherembodiments, in-phase wavefront 129 may be both coherent and collimated.Optical system 120 is configured to illuminate phase map 150 within-phase wavefront 129.

Phase map 150 is an optical element configured to adjust a phase ofin-phase wavefront 129 to form an image from the phase map at aretina-distance when phase map 150 is illuminated by in-phase wavefront129. In other words, phase map 150 is pre-recorded with a phase patternto scatter in-phase wavefront 129 as image light 173 to form a realimage directly onto the retina of a human eye. For the purposes of thedisclosure, retina-distance will be defined as the distance between thephase map and the retina of a human eye. In one embodiment, the retinadistance is less than 30 mm which is less than the nearest focusingcapability of the human eye. FIG. 1B shows a zoomed-in side viewillustration of phase map 150 and eye 199. The disclosed phase maps area made of a transparent material, in the illustrated embodiments. Thedisclosed phase maps are not active reflective spatial modulators foundin Liquid Crystal on Silicon (LCOS) technologies. Dimension D1 157 showsthe depth of phase map 150 and dimension D2 158 shows the length ofphase map 150. FIG. 3A shows a plan view of pixelated phase map 150where phase map 350 is dimension D4 357 wide and dimension D2 158 long.In one embodiment, dimension D1 157 is 1 nm, dimension D2 158 is 1 mm,and dimension D4 357 is 1 mm.

In FIG. 3A, phase map 350 includes an array of transparent pixelsarranged in rows and columns. In one embodiment, phase map 350 includesa 1000×1000 array of pixels where each pixel is 1 μm by 1 μm and phasemap 350 is 1 mm in length (D2)×1 mm in width (D4). The pixels may bebetween 0.1 μm and 40 μm, in some embodiments. The pixel size may alsobe referred to as “phase period.” In one embodiment, the pixel pitch(dimension between pixels) is non-uniform. The phase of each pixel inthe array of pixels can be adjusted such that the phase of photons fromin-phase wavefront 129 that encounter the pixel is changed by advancingor retarding (slowing down) the photons incident on the pixel relativeto the phase of wavefront 229 passing through other pixels. In theillustrated embodiment of FIGS. 1A and 1B, in-phase wavefront 129propagates orthogonal to the plane of phase map 150. In FIG. 3A,wavefront 129 is illustrated as an arrow propagating into the page,although wavefront 129 may be incident a phase map at different anglesbeside orthogonal to the plane of the phase map. Cumulatively, varyingthe phase in pixels of the array of pixels in phase map 350 willdiffract wavefront 129 to generate an image when the phase map isilluminated with wavefront 129.

One way to adjust the phase of each pixel is to vary the depth of thepixel. Adjusting the depth of a refractive medium (e.g. transparentpolymer) of each pixel changes the length of the optical path that lighttravels—and hence adjusts the phase. FIG. 3B shows a cross section often pixels in phase map 350 where the depth of the pixels has beenadjusted according to the phase pattern corresponding to the image. Eachpixel has been set according to a discrete phase level. In oneembodiment, the phase pattern has eight discrete phase levels that thepixels can be adjusted to. In other words, the depth of the refractivemedium for each pixel can have one of eight different depths. In otherembodiments, the phase pattern has three or four discrete phase levels.For generating horizontally or vertically symmetrical images, twodiscrete phase levels may be sufficient for pixels of the phase pattern.An increased number of discrete phase levels generally corresponds toincreased image quality. Although FIG. 3B illustrates discrete phaselevels with sharp edges between each pixel, full grey-scale (i.e.continuous) variation of the phase levels is achievable.

The different phase levels of the pixels are engineered to diffractwavefront 129 to form an image such as image 383 in FIG. 3C. Engineeringthe desired diffraction may include engineering the pixels to diffractwavefront 129 at different orders of diffraction to form image 383. Oncethe pixels are engineered for the desired image 383, the pixel patternthat generates image 383 is pre-recorded into the phase map so thatphase map 150 will generate image 383 on the retina when phase map 150is illuminated with wavefront 129. Image 383 includes the number “4” andtwo arrows. One arrow points in a northeast direction and one arrowpoints in a southeast direction.

Referring back to FIG. 1B, dimension D3 177 is the retina-distancebetween phase map 150 and image plane 183, which is targeted to be theretina of eye 199. The optical distance between phase map 150 and theretina is an important distance to define in order to engineer phase map150 to form an image on the retina. The internal eye optical distancebetween the retina and the corneal surface at the front of the eye(taking into the account the differing indices of refractions of thecornea and intervening elements such as the lens and vitreous humor ofan eye) is well documented. Therefore, adding the optical distance thatthe phase map will be offset from the cornea to the internal eye opticaldistance will give the total optical distance between the phase map andimage plane 183. The total optical distance may be within a range totake into account differences in eye sizes. If phase map 150 is disposedin a contact lens, the optical distance between the cornea and phase map150 may be very small (e.g. 1 mm or less). If phase map 150 is includedin a head mounted display (“HMD”), phase map 150 may be disposed 2-30 mm(or more) from the cornea.

Once the target total optical distance between the retina and the phasemap is defined, the input phase information (phase pattern) to generatean image to be coded onto phase map 150 can be calculated usingpublished algorithms or commercial optics software. After the initialcalculation of the phase map, the phase map can be altered iterativelyby utilizing inverse Fourier Transforms that converts the amplitudedomain to the phase domain. Input parameters for calculating the phaseinformation to be pre-recorded in phase map 150 may include, targettotal optical distance, the size (length, width, and depth) of the phasemap, the spectral properties (wavelength) of in-phase wavefront 129, thesize of the desired real image on the retina, the integer number ofphase levels to be utilized in the phase map, and the number of pixelsand pixel spacing (phase period) of pixels in the phase map. Thespectral properties of wavefront 129 are useful to engineer the pixelpattern that generates image 383 because the diffractive pattern of thepixels is tuned to certain wavelengths, in some embodiments. Thespectral properties of the in-phase wavefront may be the same as theemission (illumination light 107) of light source 105. The size of thedesired image on the retina is related to the Field of View that theimage will take up. In one embodiment, it is desirable for the imageformed on the retina to be approximately 20% of a Field of View of theuser/wearer of the near-eye display 100.

With the input parameters recited above, near-eye display 100 can bemodeled by commercial software and the phase map can be iterativelyadjusted (using iterative inverse Fourier Transforms) to improve theimage generated by the phase map. VirtualLab™ by LightTrans GmbH of JenaGermany is one software suite that could model near-eye display 100.

FIG. 2 illustrates an example near-eye display 200 that includes a phasemap 150, in accordance with an embodiment of the disclosure. FIG. 2shows an example optical system 220 that is one example of opticalsystem 120. Optical system 220 includes collimating element 221,receiving optical element 223, waveguide 225, and outcoupling opticalelement 227. In FIG. 2, collimating element 221 is disposed betweenlight source 105 and waveguide 225. Collimating element 221 collimatesillumination light 107. Collimating element 221 includes a Fresnel lens,in one embodiment. Receiving optical element 223 receives collimatedillumination light 222 and directs collimated illumination light 222 topropagate through waveguide 225. Waveguide 225 is fabricated from asuitable transparent material (e.g. acrylic). In one embodiment,waveguide is only 1 μm thick and 1 mm wide. Waveguide 225 may rely onTotal Internal Reflection (“TIR”) or mirror elements to guide theillumination light as the illumination light propagates throughwaveguide 225. In one embodiment, receiving optical element 223 includesa Bragg grating configured to redirect the illumination light so thatthe illumination light propagates through waveguide 225 at the properangle (that does not violate the principles of TIR, for example). InFIG. 2, receiving optical element 223 is a reflective optical element,but it is understood that receiving optical element 223 may also be atransmissive optical element in some embodiments.

Outcoupling optical element 227 is configured to outcouple theillumination light propagating through waveguide 225 and direct theillumination light to the phase map as in-phase wavefront 229.Outcoupling optical element 227 may be a Bragg grating. Outcouplingoptical element 227 is integrated into the bulk medium of waveguide 225as a volume hologram, in one embodiment. Receiving optical element 223may also be integrated into the bulk medium of waveguide 225 as a volumehologram. Outcoupling optical element 227 directs in-phase wavefront 229to phase map 150 at the proper incident angle. In one embodiment,in-phase wavefront is in-phase because waveguide 225 is phase preservingand it preserves the in-phase nature of illumination light 107 generatedby light source 105 (which may be approximately modeled as a pointsource). In one embodiment, in-phase wavefront 229 is in-phase becauseoutcoupling optical element is phase selective and outputs onlyillumination light propagating in waveguide 225 that is in-phase. Oneimportant function of optical system 220 is to deliver a predictable,in-phase wavefront 129 because phase map 150 functions optimally when itis illuminated by a wavefront for which it was designed. Althoughin-phase wavefront 129/229 is illustrated as collimated, in-phasewavefront 129/229 may be converging or diverging, in some embodiments.

Conventional wearable near-eye displays typically include amicro-display and an image relay to direct an image formed on thedisplay onto the eye. Near-eye displays include head mounted displays.However, this approach requires the optics (e.g. mirrors and lenses) ofthe image relay to direct the image to the eye without distorting theimage or shifting the colors of the image because the image directed tothe eye and the pixels of the micro-display have a one-to-onecorrespondence. Conventional wearable displays rely on amplitudemodulation of the light to generate the image for viewing. The imagerelays to deliver an image from the micro-display to the eye arethree-dimensional relays that add unwanted bulk to the wearable display.Additionally, the fabrication and assembly of precision opticalcomponents to maintain image quality adds expense to the wearabledisplays. In contrast, the disclosed near-eye displays utilize a phasemap that does not have a one-to-one correspondence between the pixels ofthe phase map and the image formed directly on the retina of the eye.Rather, the entire phase map collectively modulates the phase (ratherthan amplitude) of the in-phase wavefront to form the image on theretina. Phase map may modulate localized amplitudes of the in-phasewavefront in addition to the phase, in some embodiments. Since the imageformation happens at the phase map and image light 173 only has totravel from the phase map to the retina, a bulky and expensivethree-dimensional image relay is not required to direct the image to theeye. Instead, a two-dimensional (very thin) waveguide is all that isrequired to guide illumination light 107 to illuminate phase map 150because the waveguide does not need to guide image light as image light173 is only formed after phase map 150.

Conventional near-eye displays must also spend significant opticalresources on ensuring that the user/wearer of the near-eye display canactually focus on the image generated by the micro-display (e.g. LCD orLCOS). In the disclosed near-eye displays, the focusing ability(accommodation) of a human eye is not an obstructing design challenge asthe real image can be formed directly onto the retina from the phase mapand any required magnification can be pre-recorded directly into thephase map. Therefore, additional focusing optics are not required toallow a wearer to focus on the image and the phase map can be the lastoptical element that assists in forming the image onto the eye.Additionally, a user's contact lens or eye glass prescription can beincluded into the phase map so that the optical power required topresent an image that the wearer/user perceives as in-focus ispre-recorded into the phase map. Yet another potential advantage of thedisclosed near-eye displays is that phase maps are an efficient imagedelivery vehicle in that most (or almost all) of the light emitted bythe light source is utilized to form the image. In contrast, thefilters, polarizers, and liquid crystal of conventional micro-displaysblock or wastes a significant amount of light injected into themicro-displays to form the initial image.

As mentioned above, one way of changing the phase levels of each pixelis to vary the depth of the refractive medium of the phase map. Thephase map can be fabricated using an additive process (e.g. 3D printing)that builds up the depth of each pixel as needed or fabricated using asubtractive process (e.g. etching and photolithography) that subtractsmaterial to define the depth of each pixel. Another way to adjust thephase in each pixel is to have each pixel have the same depth, butchange the refractive index of each pixel in order to advance or retardthe photons of wavefront 129 propagating through the pixel. An additiveprocess (e.g. 3D printing) may be utilized to fabricate a phase map withpixels that have different index of refraction by using a differentrefractive material for different pixels. Alternatively, the phase mapcan be made from a refractive medium (e.g. Corning PI109) that changesin response to heat or light. Then to adjust the refractive index ofeach pixel, the pixels can be selectively radiated with a laser (togenerate heat) or light source (e.g. a UV light source) to change therefractive index of the pixel.

FIG. 4A illustrates a top view of a smart contact lens (“SCL”) 410 thatincludes control circuitry 409, light source 405, optical system 420,and phase map 450, in accordance with an embodiment of the disclosure.SCL 410 is one example of a wearable near-eye display that includes aphase map. SCL 410 includes transparent material 421 that is made from abiocompatible material suitable for a contact lens. Substrate 430 isillustrated as a substantially flattened ring disposed atop or embeddedwithin transparent material 421. In one embodiment, the flattened ringhas a diameter of about 10 millimeters, a radial width of about 1millimeter, and a thickness of about 50 micrometers.

Substrate 430 includes one or more surfaces for mounting electrical orelements such as control circuitry 409 and light source 405. In oneembodiment, substrate 430 includes a semiconductor material (e.g.silicon) and control circuitry 409 is formed in substrate 430 by way ofcommon CMOS processes. Control circuitry 409 may be an arrangement ofdiscrete logic or a microprocessor, for example. In one embodiment,substrate 430 includes a multi-layer flexible circuit board. In oneembodiment, substrate 430 is made of a rigid material such aspolyethylene terephthalate (“PET”). In one embodiment, substrate 430 ismade of flexible material such as polyimide or organic material.Substrate 430 may be disposed along an outer perimeter of SCL 410 so asnot to interfere with a viewable region of SCL 410 that a wearer of SCL410 would be looking through. However, in one embodiment, substrate 430is substantially transparent and does not substantially interfere with awearer's view, regardless of disposition location.

FIG. 4B illustrates a side view of a SCL 410 that includes controlcircuitry 409, light source 405, optical system 420, and phase map 450,in accordance with an embodiment of the disclosure. FIG. 4B showstransparent material 421 has a concave surface side 426 (eyeside)opposite a convex surface side 424 (external side). Concave surface side426 will have substantial contact with the eye of a wearer of SCL 410. Acircular outside edge 428 connects concave surface side 426 and convexsurface side 424.

When control circuitry 409 activates light source 405, light source 405injects illumination light into optical system 420 which delivers anin-phase wavefront to phase map 450. Phase map 450 diffracts thein-phase wavefront as image light 473 (by manipulating the phase of thein-phase wavefront) in an eyeward direction to form a real image on theretina of a wearer of SCL 410. SCL 410 may be weighted using similartechniques as contacts that are designed for astigmatisms to keep phasemap 450 in a consistent location and maintain a spatial orientationrelative to the eye so the image is formed with a specific orientation.

FIG. 6A illustrates a cross-section side view of an example SCL 410mounted on a corneal surface 20 of an eye 10, in accordance with anembodiment of the disclosure. SCL 410 is shown mounted under uppereyelid 30 and lower eyelid 32. FIG. 6B illustrates a zoomed-in view oflight source 405, optical system 420, and phase map 450, in accordancewith an embodiment of the disclosure. Light source 405 is disposed on aninner edge of substrate 430 to inject illumination light into opticalsystem 620. Optical system 620 delivers an in-phase wavefront to phasemap 450. Phase map 450 scatters the in-phase wavefront as image light673 in an eyeward direction to form a real image on the retina of awearer of SCL 410.

Using the elements of near-eye display 100/200 in a contact lens offersmany potential advantages. First, since image light 473/673 is formed atphase map 450, a bulky light delivery relay is not required to deliveran image from a micro-display to the eye. This allows a waveguide inoptical system 620 to be very thin (two-dimensional) since it need notbe designed to maintain an image propagating from a micro-display.Rather, optical system must merely deliver illumination light from lightsource 405 to phase map 450 as an in-phase wavefront. Additionally,phase map 450 itself can be very thin (e.g. 1 nm deep) since itmodulates the phase of the in-phase wavefront rather than exclusivelyrelying on pure amplitude modulation of light to form an image.Furthermore, modulating the phase of the in-phase wavefront also allowsphase map 450 to be transparent which will be less noticeable to awearer of SCL 410 if phase map 450 is located (at least partially) in afield of view of the wearer.

FIG. 5 illustrates a system 500 that includes a near-eye display, inaccordance with an embodiment of the disclosure. System 500 includes anear-eye display that includes light source 405, optical system 520, andphase map 550. System 500 also includes light control circuitry andlogic 409, memory 506, sensor 545, and transceiver 539. System 500 alsoincludes a base station 565 that is coupled to communicate with anetwork 585. Network 585 may be a wireless cellular network, Wide AreaNetwork (“WAN”), Local Area Network (“LAN”), or otherwise. System 500also includes a power source (not illustrated) to power the illustratedelements. The power source may include a battery and/or a photovoltaicelement that generates electrical power by harvesting light.

In system 500, control circuitry 409 is coupled to light source 405 toselectively modulate illumination light 507 emitted by light source 405.To turn on light source 405, control circuitry may send a digital signalto a control terminal of a transistor that regulates the current throughlight source 405, for example. Control circuitry 409 is coupled to readand write to memory 506. Memory 506 may store instructions for executionon control circuitry 409. Control circuitry 409 is coupled to initiate ameasurement or test by sensor 545. Sensor 545 is coupled to send themeasurement or the results of the test to control circuitry 409. Sensor545 may measure biometric data. In one embodiment, sensor 545 is aminiaturized glucose meter. Sensor 545 is disposed on substrate 430 inone embodiment of contact lens 410.

Transceiver 539 is positioned to receive communication data 567 frombase station 565. Base station is a network router, in one embodiment.Control circuitry 409 is coupled to read an output of transceiver 539and coupled to transmit data to transceiver 539 to be sent to basestation 565. Communication between transceiver 539 and base station 565may be WiFi, BlueTooth™, or other wireless communication standards orprotocols. Control circuitry 409 may initiate an action in response toreceiving communication data 567 from transceiver 539. For example,communication data 567 may be a digital word that instructs controlcircuitry 409 to activate (turn on) light source 405 in order toilluminate phase map 550 and generate an image for the eye of a user ofsystem 500. Control circuitry 409 may also initiate a measurement usingsensor 545 in response to certain communication data 567. In oneembodiment, control circuitry 409 activates light source 405 to generateimage light 573 in response to receiving a measurement from sensor 545that is above or below a given threshold. Where sensor 545 is a glucosesensor, control circuitry 409 may activate light source 405 in responseto a low glucose reading to form an image onto the retina of a user. Theimage alerts the user that her blood sugar may be low. System 500(excluding base station 565) may be implemented into a contact lens orHMD, in accordance with embodiments of the disclosure.

FIG. 7 illustrates a head mounted display (“HMD”) that may integrateportions of system 500, in accordance with an embodiment of thedisclosure. Example HMD 700 is a monocular HMD. HMD 700 includesside-arms 713, a center frame support 774, and a bridge portion withnosepiece 775. In the example embodiment shown in FIG. 7, center framesupport 774 connects the side-arms 713. HMD 700 does not includelens-frames containing lens elements in the illustrated embodiment, butother embodiments may include lens elements. An HMD is a display deviceworn on or about the head. Although FIG. 7 illustrates a specificmonocular HMD 700, embodiments of the present invention are applicableto a wide variety of frame types and styles (e.g. visor, headband,goggles).

HMD 700 may additionally include a component housing 776, which mayinclude an on-board computing system (not shown), an image capturedevice 778, and a button 779 for operating the image capture device 778(and/or usable for other purposes). Component housing 776 may alsoinclude other electrical components and/or may be electrically connectedto electrical components at other locations within or on the HMD.Component housing 776 may include light sources (not shown) positionedto inject waveguide 725 will illumination light. As discussedpreviously, waveguide 725 can be include in an optical system thatdeliver an in-phase wavefront to phase map 750 which adjusts the phaseof the in-phase wavefront to generate image light 773. Although notspecifically illustrated, the components of optical system 220 may beintegrated, as needed, into HMD 700 to generate image light 773 viaphase map 750.

Here again, using a phase map in a near-eye display allows waveguide 725to be very thin when compared to larger image relays in conventionalHMDs. And, the illustrated embodiment of HMD 700 is capable ofdisplaying an augmented reality to the user since waveguide 725 andphase map 750 may be transparent and permit the user to see a real worldimage via external scene light 755 in addition to image light 773.

FIG. 8 is a perspective view of example wearable glasses 800 (oneexample of an HMD) that may include portions of system 500, inaccordance with an embodiment of the disclosure. The illustratedembodiment of wearable glasses 800 includes lenses 845 disposed in frame825 that includes left temple arm 830 and right temple arm 840. A phasemap 850 is included with one of the lenses 845, in the illustratedembodiment. In one embodiment, both lenses 845 include a phase map andcorresponding optical system to deliver an in-phase wavefront to thephase maps so that each eye receives an image from the correspondingphase map. Phase map 850 may be planar or curved according to thecurvature of lens 845. Although FIG. 8 illustrates a traditionaleyeglass frame 825, embodiments of the disclosure are applicable to awide variety of frame types and styles (e.g. visor, headband, goggles).The frame 825 of eyeglasses 800 may also include other electricalcomponents and/or may be electrically connected to electrical componentsat other locations within or on eyeglasses 800. Frame 825 may includelight sources (not shown) positioned to inject a waveguide (notillustrated) will illumination light to illuminate phase map 850. Asdiscussed previously, the waveguide can be included in an optical systemthat delivers an in-phase wavefront to phase map 850 which adjusts thephase of the in-phase wavefront to generate image light directed towardan eye of a wearer of eyeglasses 800. Although not specificallyillustrated, the components of optical system 220 may be integrated, asneeded, into eyeglasses 800 to generate image light via phase map 850.

Multiple phase maps 850 may be included in one lens 845 of eyeglasses800. In one example, each of the multiple phase maps 850 in one lens 845may have their own waveguide and light source. Each light source can beselectively activated to illuminate (via its corresponding waveguide)its corresponding phase map to selectively display different images intothe eye. The multiple phase maps may be configured in the lenses 845 toincrease the effective eye box of the near-to-eye display. Multiplephase maps may be incorporated into the various near-to-eye displays 410and 700.

The above description of illustrated embodiments of the invention,including what is described in the Abstract, is not intended to beexhaustive or to limit the invention to the precise forms disclosed.While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various modifications arepossible within the scope of the invention, as those skilled in therelevant art will recognize.

These modifications can be made to the invention in light of the abovedetailed description. The terms used in the following claims should notbe construed to limit the invention to the specific embodimentsdisclosed in the specification. Rather, the scope of the invention is tobe determined entirely by the following claims, which are to beconstrued in accordance with established doctrines of claiminterpretation.

What is claimed is:
 1. A contact lens comprising: a biocompatiblematerial suitable to be in contact with a human eye having an eye-sideopposite an external side, wherein the eye-side is curved to fit a humaneye; a first substrate; a light source configured to emit illuminationlight, wherein the light source is coupled to or disposed within thefirst substrate; an optical system disposed to receive the illuminationlight from the light source and output the illumination light as anin-phase wavefront; and a phase map disposed to receive the in-phasewavefront output from the optical system and to adjust a phase of thein-phase wavefront to form an image at a retina-distance in response tobeing illuminated by the in-phase wavefront output from the opticalsystem, wherein the phase map includes a pre-recorded phase patterndisposed across a second substrate.
 2. The contact lens of claim 1,wherein the optical system includes: a waveguide positioned to receivethe illumination light from the light source; and an outcoupling opticalelement configured to outcouple the illumination light from thewaveguide to the phase map.
 3. The contact lens of claim 2, wherein theillumination light is in-phase when the illumination light is receivedby the waveguide, and wherein the waveguide is configured to preservethe illumination light as in-phase.
 4. The contact lens of claim 2,wherein the outcoupling optical element is configured to select in-phaselight of the illumination light propagating through the waveguide tooutput as the in-phase wavefront.
 5. The contact lens of claim 2,wherein the optical system further includes: a collimating elementdisposed between the waveguide and the light source, wherein thecollimating element collimates the illumination light; and a receivingoptical element configured to direct the illumination light through thewaveguide, wherein the receiving optical element receives theillumination light after the illumination light propagates through thecollimating element.
 6. The contact lens of claim 1, wherein the phasemap includes an array of transparent pixels and wherein each transparentpixel advances or retards photons in the in-phase wavefront according tothe phase pattern.
 7. The contact lens of claim 6, wherein eachtransparent pixel in the array of transparent pixels varies the phase ofthe photons by varying an index of refraction of the transparent pixel.8. The contact lens of claim 6, wherein each transparent pixel in thearray of transparent pixels varies the phase of the photons by varying adepth of a refractive medium of the transparent pixel.
 9. The contactlens of claim 8, wherein the depth of the refractive medium for eachtransparent pixel is set according to discrete phase levels.
 10. Thecontact lens of claim 6, wherein a pixel pitch of the transparent pixelsin the array of transparent pixels is non-uniform.
 11. The contact lensof claim 1 further comprising: control circuitry coupled to the lightsource to modulate the illumination light in response to input data. 12.The contact lens of claim 11 further comprising a transceiver coupled tothe control circuitry, wherein the input data is received from thetransceiver.
 13. The contact lens of claim 11 further comprising asensor coupled to the control circuitry, wherein the input data isreceived from the sensor, and wherein the sensor is configured tomeasure biometric data from a wearer of the contact lens.
 14. Thecontact lens of claim 1, wherein the contact lens is weighted tomaintain a spatial orientation of the phase map in relation to the humaneye.
 15. A system comprising: a base communication station configured tosend wireless data; and a smart contact lens comprising: a transparentmaterial having an eye-side opposite an external side, wherein thetransparent material includes a biocompatible material suitable to be incontact with a human eye, and wherein the eye-side is curved to fit thehuman eye; a light source configured to emit illumination light; anoptical system disposed to receive the illumination light from the lightsource and output the illumination light as an in-phase wavefront; and aphase map positioned to receive the in-phase wavefront from the opticalsystem and to adjust a phase of the in-phase wavefront to form an imageat a retina-distance in response to being illuminated by the in-phasewavefront, wherein the phase map includes a pre-recorded phase patterndisposed across a substrate to that generates the image when illuminatedby the in-phase wavefront; and control circuitry coupled to modulate thelight source in response to receiving the wireless data from the basecommunication station.
 16. The system of claim 15, wherein the opticalsystem includes: a waveguide disposed to receive the illumination lightfrom the light source; and an outcoupling optical element configured tooutcouple the illumination light from the waveguide toward the phase mapas the in-phase wavefront.
 17. The system of claim 16, wherein theillumination light is in-phase when the illumination light is receivedby the waveguide, and wherein the waveguide is configured to preservethe illumination light as in-phase.
 18. The system of claim 16, whereinthe outcoupling optical element is coupled to select in-phase light tooutput as the in-phase wavefront.
 19. The system of claim 16, whereinthe outcoupling element is integrated into a bulk medium of thewaveguide as a volume or surface hologram.
 20. The system of claim 15,wherein the optical system is sealed within the transparent material.